Pre Algebra Writing Inequalities

In this lesson our instructor talks about writing inequalities. She talks about inequality, system of inequalities, and solution of an inequality. She does several examples of writing inequality and system of inequalities. She talks about identifying solutions of an inequality. Four extra example videos round up this lesson.

Writing Inequalities

A mathematical sentence that contains one of the following symbols is an inequality.

Verbal Description

Symbol

Is less than

<

Is greater than

>

Is less than or equal to

≤

Is greater than or equal to

≥

Is not equal to

≠

The solution of an inequality is any value that makes the inequality true. The graph of an inequality shows that an inequality can have many solutions. A closed circles indicates that a value is included. An open circle indicates that a value is not included.

Writing Inequalities

Write an inequality for the verbal description, The price p is more than $ 3. Graph the description on a number line.

p > 3

Write an inequality for the verbal description, A wage w is at least $ 9.30. Graph the description on a number line.

w ≥ 9.30

During a recent storm, the wind speed was greater than 44 mph but less than 56 mph. Write an inequality to represent this situation and graph using a number line.

s > 44, s < 56

44 < s < 56

A price of a room at a motel is at least $ 40.00 and at most $ 125.00. Write an inequality and graph.

p ≥ 40, p ≤ 125

40 ≤ p ≤ 125

To meet a company's standards of quality, the weight of a burrito has to be within 0.5 ounces of the weight listed on the packaging. The burrito is listed as 8.5 ounces. Write an inequality describing the permissible weights of the burrito and graph.

8 ≤ b ≤ 9

You need to have taken at least 10.5 units of introductory psychology courses before you can become a psychology major. Write an inequality representing the situation. Can Lillian, who has taken 3 introductory courses at 3 units each, declare her psychology major?

u ≤ 10.5

Lillian has taken 9 total units: 9 < 10.5

u ≤ 10.5 No

Write an inequality for the verbal description, A number x is not negative. Graph the inequality.

x ≥ 0

Write a system of inequalities for this situation: The temperature should be less than 90° F but at least 75° F. Graph the solution.

75° F ≤ t < 90° F

Write an inequality for 4 is at least half of a number.

ät least" means " ≥ "

ä number" is represented by "x"

4 ≥ [1/2]x

Write and use an inequality to solve the problem. A child must be at least 4 feet 11 inches to not need a child seat in a vehicle. Use the table to identify the children that need a child seat.

*These practice questions are only helpful when you work on them offline on a piece of paper and then use the solution steps function to check your answer.

Answer

Writing Inequalities

Lecture Slides are screen-captured images of important points in the lecture. Students can download and print out these lecture slide images to do practice problems as well as take notes while watching the lecture.